1. Field of the Invention
The present invention relates to an external wall of a building, and more particularly, to external wall panel units for saving energy and an external wall structure system using the same, which can recycle rainwater after collecting rainwater from the external wall of the building, reduce temperature of the external wall, discharge out heated air inside the external wall and effectively discharge out exhaust indoor air through a duct, and function as an awning according to a direction of the sun.
2. Background Art
Recently, many new tall buildings have been built in order to accommodate many persons and facilities in a limited or small site.
An RC structure and an SRC structure have been widely used to build such tall buildings, and the SRC structure mainly takes curtain walls for the external wall.
The curtain wall is typically comprised of external wall units mainly made of glass, metal or stone.
Such curtain walls have several problems in that it increases carbon emissions and is uneconomical since there is a need to operate a cooling system because of a sudden rise of the indoor temperature of the building in the summer season with a lot of sunshine and high outdoor temperature and there is a need to operate a heating system because of a sudden drop in the indoor temperature of the building in the winter season with reduced sunshine or low outdoor temperature.
Furthermore, recently, there are many attempts to collect rainwater in case of rain to use it as toilet water or ornamental water so as to reduce carbon emissions on the basis of green growth.
However, till now, there have been made attempts to collect rainwater on the roof or the rooftop of a building but there does not have been made any attempts to collect a lot of rainwater flowing along the external wall of the building.